CSC Seminar - Guillaume Lajoie
Friday, Sep 20 - 2:30pm to 3:45pm
CSC Weekly Seminar
Friday, September 20, 2013
TASC-2, RM 8500
Speaker: Guillaume Lajoie
Chaos and reliability in fluctuation-driven, balanced spiking networks: from dynamics to information content.
The question of reliability arises for any dynamical system driven by an input signal: if the same signal is presented many times with different initial conditions, will the system entrain to the signal in a repeatable way? Reliability is of particular interest in large, randomly coupled networks of excitatory and inhibitory units. Such networks are ubiquitous in neuroscience, but are known to autonomously produce strongly chaotic dynamics – an obvious threat to reliability. Here, we show thatsuch chaos also occurs in the presence of weak and strong stimuli. However, even in the chaotic regime, intermittent periods of highly reliable spiking often coexist with unreliable activity. We propose a framework to better understand these complex dynamics, leveraging results from random dynamicalsystems (RDS) theory, by establishing the effect of the underlying chaoticattractor's geometry on output spike trains. The impact of this phenomenon on the mutual information between an input signal and the network's spike output will also be discussed.